Door latching and locking device



July 12, 1966 c. J. DARGENE DOOR LATCHING AND LOCKING DEVICE 5Sheets-Sheet 1 Filed July 1, 1964 July 12, 1966 c. J. DARGENE DOORLATCHING AND LOCKING DEVICE 5 Sheets-Sheet 2 Filed July 1, 1964 e n I Wd a C A7 w W 11,41 .L aw

UTTOWEY/ July 12, 1966 c. J. DARGENE DOOR LATCHING AND LOCKING DEVICE 5Sheets-Sheet 5 Filed July 1, 1964 MVEZ QT'OK Car-1 IS United StatesPatent 3,266,813 DOOR LATCHING AND LOCKING DEVICE Carl J. Dargeue,Rockford, Ill, assignor to Ameroek Corporation, Rockford, Ill., acorporation of Illinois Filed July 1, 1964, Ser. No. 379,670 7 Claims.(Cl. 200-6164) This invention relates to devices for latching andlocking the door or a cabinet for an automatic dishwasher or the like intightly closed condition prior to initiation of the dishwashing cycle,and including generally a strike mountable on the cabinet for latchingengagement with a bolt mountable on the door, and a manual operatoraccessible from outside the door for locking the closed door andactuating a control switch to condition the dishwasher for operation.

The general object of the present invention is to provide a new andimproved latch of the foregoing character which latches and unlatchesautomatically in response to closing and opening motions of the door,tight- 1y locks and seals the door preparatory to activation of thedishwashing apparatus, and effects a positive lockout of the controlswitch in a novel and simple manner whenever the door is unlocked.

A more specific object is to latch and unlatch the bolt as an incidentto its engagement with the strike during closing and opening of thedoor, and to lock the bolt in the latched position with a simple slideoperator movable back and forth on the door between locking andunlocking positions.

Another object is to utilize the unlatched bolt as a stop for preventinglocking and switch-actuating movement of the slide when the door isopen.

A further object is to utilize the locking motion of the slide to insuretight sealing of the door before the dishwashing apparatus is activated.

Ather objects and advantages of the invention will become apparent fromthe following detailed description taken in connection with theaccompanying drawings, in which FIGURE 1 is a fragmentary perspectiveview of a dishwasher equipped with a latching and locking deviceembodying the novel features of the present invention.

FIG. 2 is an enlarged fragmentary cross-sectional View takensubstantially along the line 2-2 of FIG. 1.

FIG. 3 is a fragmentary cross-sectional view taken substantially alongthe line 33 of FIG. 2.

FIG. 4 is a fragmentary cross-sectional view taken substantially alongthe line 44 of FIG. 2.

FIG. 5 is a view similar to FIG. 3 with the parts in moved positions.

FIG. 6 is an enlarged perspective view of the bolt.

FIG. 7 is a fragmentary perspective view of the latching and lockingmechanism.

FIG. 8 is a fragmentary cross-sectional view taken substantially alongthe line 88 of FIG. 4.

As shown in the drawings for purposes of illustration, the invention isembodied in a device 10 for latching the door 11 of a cabinet 12 for anautomatic dishwasher or the like releasably in a closed positionrelative to the cabinet frame and locking the door in a tightly sealedcondition prior to operation of the dishwashing apparatus (not shown).In general, the device comprises a strike 13 herein mounted on thecabinet along one side of the access opening 14 for engagement with abolt 15 on the door, and an operator 17 accessible from outside the doorand manually movable back and forth between two positions to lock andunlock the door. To prevent actuation of the dishwashing apparatus whenthe door is open or free to open, a switch 18 in the control circuit ofthe apparatus is controlled by the operator and conditions 3,260,813Patented July 12, 1966 the circuit for operation only when the door isclosed and tightly sealed.

In this instance, the latching device 10 is applied to a dishwashercabinet 12 mounted under a counter 19 and having a front opening, hollowsheet metal door 11 which, in the closed position shown in the drawings,engages and seals against a resiliently compressible gasket 20 extendingaround all sides of the cabinet opening. The bolt 15 is pivoted forrotation in a plane perpendicular to the plane of the door on a base orframe 21 mounted inside the door adjacent the top edge of the latter,and the strike 13 is mounted on the cabinet along the top of the cabinetopening and projects into the door through an opening 22 in the sealingportion of the inner panel 23 of the door.

Herein, the strike 13 is a zinc die casting having a hook-shaped outerend 24 disposed in the plane of the bolt 15 when the door is closed andsupported on a base 25 disposed inside the flange 37 (see FIG. 2)forming the rim of the dishwasher tub which defines the top of thecabinet opening 14. The strike is secured to the rim by means of screws28 inserted through alined holes in the rim and a spacer 29 between thebase and the rim, and threaded into alined holes in the base (see FIG.3).

The present invention contemplates a new and improved device 10 of theforegoing character which latches and unlatches automatically inresponse to closing and opening motions of the door 11, tightly locksand seals the door preparatory to activation of the dishwashingapparatus, and effects a positive lockout of the control switch 18 in anovel and simple manner whenever the door is unlocked. For thesepurposes, the bolt 15 is pivoted for rotation between angularly spacedlatched and unlatched positions as an incident to engagement with thestrike 13 during closing and opening motion of the door, and theoperator 17 is a slide including means for insuring that the door istightly closed, locking the bolt in the latched position, and actuatingthe control switch as the slide is moved in one direction relative tothe latched bolt. Moreover, when the door is open, the unlatched boltblocks locking movement of the slide and thus positively preventsactuation of the control switch.

'In this instance, the base or frame 21 (see FIG. 7) on which the bolt15 is pivoted is a sheet metal stamping having a vertical body portion30 fastened to the adjacent portion of the inner panel 23 of the door byscrews 31 and formed with two horizontal flanges 32 and 33 projectingoutwardly from the top and bottom edges of the body portion. The upperflange 32 supports the bolt and its spring-loading mechanism while thelower flange 33 cooperates with the upper flange in supporting andguiding the locking slide 17. An integral extension 34 of the lowerflange projects inwardly toward the inner panel of the door in the planeof the lower flange to provide a support for the control switch 18.

Herein, the bolt 15 is disposed above the right end portion 35 (FIG. 5)of the upper flange 32 between the latter and the similarly shaped endportion 37 of the top wall 38 of a box-like spring housing 39 mounted onthe upper flange and having an open side facing toward the bolt. Thehousing is secured to the upper flange by two rivets 40 and 41 (FIG. 7)extending through alined holes in the flange and the top housing wall,and is fastened to the door panel 23 by screws 42 (FIG. 5) threaded intothe inside wall 43 of the housing. The shank of the rivet 40 extendsthrough a hole 44 (FIG. 6) in the bolt and thus defines the pivotal axisof the bolt.

The bolt 15 is a generally triangular block of suitable material such asDelrin and is notched on the side that faces toward the strike in theunlatched position (FIG. 5) to form a heel 45 on one side of the notchand a toe 47 on the other side. The Wall 48 of the notch forming oneside of the heel is positioned for engagement with the outer end 49 ofthe strike 13 as the door 11 is closed and is shaped to rock the boltclockwise about its axis upon continued inward movement of the doorafter the heel engages the strike, thereby swinging the toe and thenotch wall 50 clockwise toward their latching positions behind the hook24 on the end of the strike. Similarly, when the bolt is latched and thedoor is pulled outwardly, the hook coacts with the notch wall 55) torotate the bolt counterclockwise and back toward the unlatched position.

The bolt is held yieldably in both the latched position and theunlatched position by means of a springloaded plunger comprising a guiderod 51 projecting loosely at one end through a hole 52 in the side wall53 of the housing 39 opposite the bolt, and carrying a head 51 on theother end of the rod pivotally connected to the bolt by means of a jointcomprising a generally cylindrical lug 54 formed on the adjacent side ofthe bolt and rotatably received in a vertically elongated groove 55 ofsemi-circular cross-section in the plunger head. A coiled spring 57telescoped over the rod and compressed between the housing wall 53 andthe plunger head urges the latter generally to the right as viewed inFIGS. 4 and 5.

It will be seen that the spring-loaded plunger and the pivoted bolt 15cooperate to form a so-called toggle latch in which the effectivedirection of the spring force on the bolt reverses as the latter passesin either direction through an intermediate angular position in whichthe bolt axis, the pivot joint, and the pivotal axis defined by the hole52 and the guide rod 51 are alined with the longitudinal axis of thespring 57. When the joint is offset in one direction from this angularposition as shown in FIG. 5, the spring urges the bolt counterclockwisetoward the unlatched position, while in the other direction of offset(FIG. 4), the spring urges the bolt toward the latched position.

To limit rotation of the bolt in each direction, stop surfaces 58 and 59are formed on the bolt to abut against opposed stop surfaces 60 and 61on the frame. Herein, the bolt surfaces comprise shoulders formed onboth the top and bottom sides of the bolt, conveniently in a commonplane perpendicular to the plane of rotation of the bolt by reducing thethickness of the bolt as shown in FIG. 6. The frame surfaces 60 and 61are formed by angularly offset edges of the end sections 35 and 37straddling the bolt. In the unlatched position of the bolt, the spring57 holds the shoulders 58 against the vertically alined edges 60 of thewalls 37 and the upper flange 35. After the bolt is rotated clockwisefrom this position past the intermediate angular position, the springurges the bolt clockwise toward the position in which the shoulders 59engage the alined edges 61 of the housing wall and the upper flange.

With the bolt enclosed in the hollow door structure, there is no dangerof movement of the bolt except as a result of engagement with the strike13 projecting through the opening 22 in the inner panel of the door. Thebolt latches and unlatches automatically as an incident to closing andopening of the door and, when latched, holds the door releasably in theclosed position with the inner sealing surfaces of the door pressedagainst the sealing gasket with a force determined by the spring 57.

As shown most clearly in FIG. 7, the lock slide 17 is a one-piece sheetmetal stamping of L-shaped cross-section formed by a flat horizontalupper section 17 immediately beneath the upper flange 32 of the frameand a fiat vertical section ll7 extending downwardly adjacent the framebody to the top of the lower flange 33. The lower edge of the verticalsection rests on top of the lower flange and is slidable on the latteralong a path parallel to the plane of the door. The lower edge of theslide is guided in a slot formed between two eyebrows 62 bent upwardlyfrom the lower flange on opposite sides of the slide, and the horizontalsection is guided by two pins alined longitudinanlly of the slide andextending downwardly from the upper frame flange through two alinedslots 63 extending longitudinally of the slide. Herein, one of the pinsis the shank of a rivet 64 having a head below the horizontal slidesection and an upset end above the upper frame flange 32, and the otherpin is the depending lower end portion of the rivet pivoting the bolt Hon the frame. Two bushings 65 (FIG. 8) are telescoped onto the guidepins and formed with center portions that fit snugly in the slots 63 andintegral annular flanges overhanging the top of the slide. Plasticwashers telescoped onto the guide pins below the horizontal section fitsnugly against the underside of the horizontal section.

To prevent rattling and objectionable looseness of the slide 17 inservice use, a spring wire 67 (FIGS. 2 and 8) is disposed between theframe body 39 and the vertical slide section 17* with its free endsfastened to the body and its generally V-shaped outer end portionpressed against the adjacent side of the slide to urge the slideoutwardly against the outer eyebrow 62 and the inner sides of thebushings 65. Thus, the spring produces frictional resistance to back andforth movement of the slide.

Integral with and projecting outwardly from the slide 17 adjacent itsright end as viewed in FIG. 7 is a lug 68 which carries a knob 69disposed outside the door and providing a hand grip for manual operationof the slide. As shown in FIG. 2, the lug is offset downwardly from theplane of the horizontal slide section 17 and projects outwardly beneaththe depending outer flange 7t) of the door structure at the top of arecess '71 in the outer door panel. The depending flange masks theopening into the door at the top of the recess. With this arrangement,the slide is movable back and forth relative to the bolt 15 by means ofthe knob 69, from the unlocking position in which the right ends of theslots 63 abut against the associated guide bushings 65 to the lockingposition in which the left ends of the slots abut against the bushings.

The control switch 18 is enclosed in a box-like case fastened to theinwardly extending lower flange 34 of the frame 31 by screws 72 (FIG.2), and is provided with an operating arm 73 in the form of a flatspring plate projecting through the opening 74 (FIG. 7) in the framebody 30 and inclined across the path of the vertical slide section 17 inthe path followed by the vertical wall 75 of a notch in the lowerright-hand corner of the vertical section as the slide moves from leftto right along the frame. The notch wall earns the arm inwardly as itslides along the arm, and this inward movement of the arm depresses theswitch button 77 (FIG. 3) to activate the dishwashing apparatus. As theslide is returned to the left, the arm is permitted to spring back toits initial position thereby releasing the button to deactivate theapparatus.

The important action of the bolt '15 and the slide 17 in sealing andlocking the door 11, and also in preventing actuation of the switch 18when the door is not sealed, is achieved through the coaction of opposedsurfaces on the slide and the bolt for preventing movement of the slidetoward the locking and switch-actuating position whenever the bolt isunlatched, camming the latched bolt into a tight-sealing latchedposition as the slide is shifted toward its locking position, andpositively locking the bolt in this position when the bolt is disposedin the locking posit-ion. For these purposes, a lug 78 is formed on thebolt in position to project outwardly into a blocking position acrossthe path of an abutment surface 79 on the slide when the bolt isunlatched. As the bolt swings toward the latched position, the lugswings out of the path of the abutment surface and comes to rest in thepath of a cam surface 80 on the slide shaped to cam the lug and the boltclockwise about the bolt axis and thereby lift the bolt farther in thelatching direction beyond the latched position determined by the sealingforce exerted by the spring 57. Finally, a locking surface 81 on theslide is brought into a position blocking rotation of the bolt out ofthe tight-sealing position.

Herein, the surfaces 79, 80, and 81 are formed on a flange 82 upstandingfrom the outer edge of the horizontal slide section 17 adjacent theright end of the latter as viewed in FIGS. 3, 4, .5 and 7 and movablewith the slide along a path adjacent the outer side of the bolt 15. Theabutment surface 79 is simply the right end of the flange and is alinedwith the left side surface 83 of the lug 78 when the bolt is unlatchedas shown in FIG. 5. With the shoulders 58 engaging the stop edges 60,the lug cannot swing to the right and thus constitutes a positive stopfor the locking slide.

As the bolt 15 is rotated toward the latching position by the strike 13and the spring 57 during closing of the door 11, the lug 78 swings outof the path of the end 79 of the flange 82 and comes to rest when theforce exerted on the strike by the spring equals the resistance exertedby the compressed sealing gasket 20, approximately in the position shownin FIG. 3 in which the end of the lug is in the path of the right endportion of the flange, the inner surface 80 of this portion beinginclined outwardly and to the right relative to the direction ofmovement of the slide. Thus, upon movement of the slide to the right,the inclined surface engages the lug and earns it inwardly to rock thelatching surface 50 of the bolt outwardly and effect a drawing-in of thedoor and a further compression of the sealing gasket to insure a tightseal all around the door.

After the left end of the cam surface 80 passes the end of the lug 78,the bolt 15 is in the tight-sealing latched position and thereafter isheld in place by the locking surface 81 on the left end portion of theflange 82. This surface lies in flat face-to-face engagement with theouter side of the bolt adjacent the lug and thus blocks counterclockwiserotation of the bolt so long as the slide is left in the lockingposition. When the slide is returned to the left, the bolt is releasedand permitted to return to the latched but unlocked position (FIG. 3) sothat an outwardpull on the door will unlatch and open the latter. Ofcourse, this motion of the slide releases the switch arm 73 todeactivate the switch 18 prior to unlocking of the bolt.

From the foregoing, it will be seen that the improved locking andlatching device 10 operates with a positive action to seal and lock thedoor 11 prior to initiation of the dishwashing cycle. Moreover, theunlatched bolt 15 constitutes a positive stop preventing actuation ofthe switch 18 by inadvertent movement of the slide 17 when the door isopen, and the bolt latches and holds the door independently of the slidewhenever the door is closed.

I claim as my invention:

1. In a device for latching and locking a door releasably in a closedposition relative to a frame, the combination of, a strike mountable onsaid frame and having a hooked outer end disposed in a planeperpendicular to the closed position of said door, a base mountable onsaid door adjacent said outer end, a generally triangular bolt pivotedon said base for rotation in said perpendicular plane in one directionfrom an unlatched position successively through intermediate, latchingand tight-scab ing positions, said bolt having a notch in the inner sidethereof facing said strike as the door is closed with the bolt in saidunlatched position, said notch having an inwardly facing wall forming aheel engageable with said strike and shaped to rock the bolt throughsaid intermediate position, said notch also forming a toe on said boltswingable in behind said hooked end into an outwardly facing position tolatch the door as the bolt rocks from said intermediate position to saidlatched position, a spring acting between said bolt and said frame andoperable to urge the bolt from said intermediate position toward saidlatched position and exert a predetermined outward latching force onsaid hooked end, a locking slide, means on said frame guiding said slidefor back and forth lateral movement thereon along a first path outerside of said bolt, a lug on said bolt disposed across said second pathwhen the bolt is in said unlatched position, thereby to block movementof the slide to said locking position, an outwardly inclined cam surfaceon said flange engageable with said lug when said bolt is in saidlatched position and shaped to cam the bolt farther in said onedirection into said tight-sealing position, and an inwardly facinglocking surface on said flange positioned to block unlatching rotationof said cam when said slide is in said locking position.

2. In a device for latching and locking a door releasably in a closedposition relative to a frame, the combination of, a strike mountable onsaid frame adjacent the closed position of said door, a base mountableon said door, a bolt pivoted on said base for rotation in a planeperpendicular to the plane of said door between latched and unlatchedpositions, latching means on said strike and said bolt operable inresponse to closing of the door to rotate said bolt from said unlatchedposition to said latched position, unlatching means on said strike andsaid bolt operable in response to opening of the door to rotate saidbolt to said unlatched position, a manually operable looking slidemounted on said base for back and forth sliding movement along apredetermined path parallel to the plane of said door between lockingand unlocking positions and remaining in said unlocking position duringlatching and unlatching of said bolt, a switch operator positioned alongsaid path, means on said slide for engaging and actuating said operatoras said slide moves to said locking position, an abutment surface onsaid bolt disposed in said path when the bolt is in said unlatchedposition thereby to block movement of said slide toward said lockingposition and prevent actuation of said operator, said abutment surfacebeing swingable out of said path as said bolt rotates toward saidlatching position, and abutment surfaces on said slide and said boltdisposed in opposed relation when the bolt is in said latched positionand said slide is in said locking position thereby to lock said bolt insaid latched position.

3. In a device for latching and locking a door releasably in a closedposition relative to a frame, the combination of, a strike mountable onsaid frame, a bolt mountable on said door for rotation between latchedand unlatched positions, latching means on said strike and said boltengageable as said door is closed and operable in response to closing ofthe door to rotate said bolt from said unlatched position to saidlatched position, unlatching means on said strike and said boltengageable as said door is opened and operable in response to opening ofthe door to rotate said bolt to said unlatched position, a lockingmember manually movable back and forth along a predetermined path onsaid door between locking and unlocking positions, a switch having anoperator positioned along said path, means on said member for engagingsaid operator and actuating said switch as said member moves to saidlocking position, first abutment surfaces on said bolt and said lockingmember disposed in opposed relation when said member is in said lockingposition and said bolt is in said latched position thereby to blockrotation of said bolt out of said latched position, and second abutmentsurfaces on said bolt and said looking member disposed in opposedrelation when said member is in said unlocking position and said bolt isin said unlatched position thereby to block movement of said lockingmember to said locking position and prevent actuation of said switchwhen said door is open.

4. In a device for latching and locking a door releasably in a closedposition relative to a frame, the combination of, a base mountable onsaid door, a bolt pivoted on said base for rotation between successiveangularly spaced unlatched, latched and tight-sealing positions, springmeans acting on said bolt when the latter is in said unlatched andlatched positions, a locking slide guided on said base for back andforth manual movement between locking and unlocking positions along apath generally parallel to the plane of said door and adja cent one sideof said bolt, means on said bolt for engaging a strike and latching saiddoor when the bolt is in said latched position and the slide is in saidunlocking position, a cam on said slide engageable with said bolt whenthe latter is in said latched position and as the slide moves towardsaid locking position and operable during such movement to rotate thebolt into said tight-sealing position, and means on said slide forholding said bolt in said tight-sealing position when the slide is insaid locking position.

5. A device as defined in claim 4 further including abutment means onsaid bolt and said slide coacting when said bolt is in said unlatchedposition to block movement of said slide to said locking position.

6. In a device for latching and locking a door releasably in a closedposition relative to a frame, the combination of, a strike mountable onsaid frame, a bolt mountable on said door for rotation between latchedand unlatched positions, latching means on said strike and said boltengageable as said door is closed and operable in response to closing ofthe door to rotate said bolt from said unlatched position to saidlatched position, unlatching means on said strike and said boltengageable as said door is opened and operable in response to opening ofthe door to rotate said bolt to said unlatched position, a lockingmember manually movable back and forth on said door between locking andunlocking positions and remaining in said unlocking position duringrotation of said bolt, first abutment surfaces on said bolt and saidlocking member disposed in opposed relation when said member is in saidlocking position and said bolt is in said latched position and coactingto block rotation of said bolt out of said latched position, and secondabutment surfaces on said bolt and said locking member disposed inopposed relation when said member is in said unlocking position and saidbolt is in said unlatched position and coacting to block movement ofsaid locking member to said locking position.

7. In a device for latching and locking a door releasably in a closedposition relative to a frame, the combination of, a strike mountable onsaid frame adjacent the closed position of said door, a bolt mountableon said door for rotation between latched and unlatched positions,spring means acting on said bolt in said closed position to urge meansacting on said bolt in said closed position to urge the bolt toward saidlatched position, said spring means reversing its direction of action assaid door is opened and thereafter urging said bolt toward saidimlatched position, a locking member manually movable back and forth onsaid door between locking and unlocking positions, first abutment meanson said bolt and said locking member for blocking rotation of said boltout of said latched position when said member is in said lockingposition, and second abutment means on said bolt and said locking memberfor blocking movement of said locking member to said locking positionwhen said bolt is in said unlatched position.

References Cited by the Examiner UNITED STATES PATENTS 1,372,000 3/1921Anderson 292-498 3,007,479 11/1961 Jacobs et al. ZOO-61.68

3,011,816 12/1961 Noord.

BERNARD A. GILHEANY, Primary Examiner.

J. J. BAKER, Assistant Examiner.

4. IN A DEVICE FOR LATCHING AND LOCKING A DOOR RELEASABLY IN A CLOSEDPOSITION RELATIVE TO A FRAME, THE COMBINATION OF, A BASE MOUNTABLE ONSAID DOOR, A BOLT PIVOTED ON SAID BASE FOR ROTATION BETWEEN SUCCESSIVEANGULARLY SPACED UNLATCHED, LATCHED AND TIGHT-SEALING POSITIONS, SPRINGMEANS ACTING ON SAID BOLT WHEN THE LATTER IS IN SAID UNLATCHED ANDLATCHED POSITIONS, A LOCKING SLIDE GUIDED ON SAID BASE FOR BACK ANDFORTH MANUAL MOVEMENT BETWEEN LOCKING AND UNLOCKING POSITIONS ALONG APATH GENERALLY PARALLEL TO THE PLANE OF SAID DOOR AND ADJACENT ONE SIDEOF SAID BOLT, MEANS ON SAID BOLT FOR ENGAGING A STRIKE AND LATCHINGPOSITIONS, A LOCKING SLIDE GUIDIN SAID LATCHED POSITION AND THE SLIDE ISIN SAID UNLOCKING POSITION, A CAM ON SAID SLIDE ENGAGEABLE WITH SAIDBOLT WHEN THE LATTER IS IN SAID LATCHED POSITION AND OPERTHE SLIDE MOVESTOWARD IS IN SAID LOCKING POSITION AND OPERABLE DURING SUCH MOVEMENT TOROTATE THE BOLT INTO SAID TIGHT-SEALING POSITION, AND MEANS TO SAIDSLIDE FOR HOLDING SAID BOLT IN SAID TIGHT-SEALING POSITION WHEN THESLIDE IS IN SAID LOCKING POSITION.